Integration of DECT and OSI to support mobile computing applications

DECT is the European standard for digital cordless telecommunication. Currently, most DECT systems have been established as standard PABX islands only. However, emerging application areas for DECT networks include data communication oriented mobile computing, making OSI conformance a major issue. This paper presents an approach towards the integration of mobile and fixed OSI-based networks using DECT as an example. Problems to be addressed include the registration, tracking and localization of mobile users roaming across cooperating DECT islands, in order to provide network-wide reachability and service access. We propose the ITU-T X.500 directory service as the natural solution to this problem. Using X.500 enables mapping of a DECT international portable users identity onto the user's current location. After briefly introducing the DECT and the X.500 standard, different schemes for location management using X.500 are discussed. Once the X.500 directory system is established, it can be accessed and utilized by telecommunication services and mobile applications. Examples include wireless access to an overall X.400 service as well as trading services for X.9tr based mobile distributed computing applications.